The answer is A I am pretty sure. This is because in choice B, you would be dividing 7 and the sum of x + 5. In choice C you would not be multiplying 7 and the sum of x + 5. When he question asks for the product, it is asking for you to multiply. In choice D you would not just be squaring y, you would be squaring 2xy, which is not what we want. We only want to square y, therefore I believe the correct answer is A.
2 1/2 * 5 = 12 1/2 cups of flour are needed to make 5 batches
5/2 * 5/1=25/2 or 12 1/2 cups
We have 60 gallons of 20% antifreeze.
How much 70% antifreeze do we add to get 60% antifreeze?
We'll make "x" the gallons of 70% we must add.
.20 * 60 + .70 x = .60 * (60 + x)
12 + .70x = 36 + .60x
.10x = 24
x = 240 gallons of 70% antifreeze.
Source
1728.com/mixture.htm (see example B)
If the number you are rounding is followed by 5, 6, 7, 8, or 9, round the number up (+1).
If the number you are rounding is followed by 0, 1, 2, 3, or 4, round the number down (no change).
GCF = -c^2d^3
Factors are -c^2d^3(8c^3d^3 + 27c^2d + 24)
